Pain in the inner side of the upper arm of the left arm can be seen in trauma, enlarged lymph nodes, nerve root cervical spondylosis, etc., which can be relieved by conservative treatment or surgical treatment according to the cause of the disease. 1. Trauma: subcutaneous bleeding or fracture caused by extrusion, indirect violence, etc., resulting in pain in the above area, which can be relieved by rest, braking, oral ibuprofen and other medications, and reset and fixation if necessary. 2. Enlarged lymph nodes: Due to the distribution of lymph nodes in the lower part of the upper arm, when there are infections and inflammations, the lymph nodes can be enlarged with pain, which can be treated with anti-inflammatory drugs such as ceftazidime. 3. Neurogenic cervical spondylosis: radiating pain in the above areas can also occur at the onset of the disease, which can be treated conservatively with medicines such as methylcobalamin and sodium lorsoprofen, and surgically if necessary. In addition, other causes of pain in the above areas should be ruled out, and it is recommended to consult a doctor in time to avoid delaying the condition.